One of the important aspects of this study is the evaluation of uncertainties, making it possible to quantify the influence of various approximations – also essential for the modeling of physical phenomena, on numerical calculations. The objective of this internship is to estimate the impact of approximations made in Density Functional Theory (DFT) on the calculation of the optical properties of a medium. In particular, we will endeavor to estimate the uncertainty in the opacity through the use of a pseudo-potential in the Projector Augmented Wave (PAW) formalism when calculating the electronic configuration of the material considered.